This invention relates to spray cooled furnace systems, e.g. electric arc furnace systems, and more particularly to an assembly for inclusion in a closure member of the furnace system to provide relief of thermal stress at the site of inclusion of the assembly in the closure member.
Spray cooled electric furnace systems of the type disclosed in U.S. Pat. Nos. 4,715,042, 4,815,096 and 4,849,987 involve the spray cooling of furnace closure elements, e.g. roofs and side walls, which are unitary, i.e. formed into one piece, and have a generally frusto-conical shape in the case of roofs, or generally cylindrical or oval in the case of a furnace side wall or other closure element. Due to the geometry of furnace electrodes and oxygen lances, variations in heating of the furnace, and the like, a particular relatively discrete region of the surface of a spray cooled closure element can be exposed to unusually high temperature and become thermally stressed with the risk of failure at such region.
Since the furnace systems as above described have unitary, one-piece, carbon steel closure elements, it is not possible to use replaceable, removable sections or panels of different, e.g. higher thermal conductivity to address the situation.
It is therefore an object of the present invention to provide means for relieving thermal stress in a unitary spray cooled steel closure element of a furnace system.